https://usage-reporter.duplicati.com/ shows more B2 API users than S3 API users, and I shudder at the idea of leading them all through a technically challenging migration. Keeping B2 may be easier, though possibly when someone tests their S3 API, some S3 benefits may emerge that aren’t currently clear…
One technical flaw in the current B2 code is that retries aren’t done quite as they want. S3 may fix that.